Water pipe drain ing - apparatus



Nov. 4, 1952 P. w. ROBERT$ WATER PIPE DRAINING APPARATUS Filed Aug" 51949 INVENTOR PAUL. W ROB'RTS &

ATTORNDIS Patented Nov. 4, 1952 WATER PIPE DRAIN ING APPARATUS Paul w.Roberts, Burnaby, British Columbia,

Canada Application August 5, 1949, Serial No. 108,755

' 1 Claim. (01. 137-107) This invention relates to apparatus fordraining I a water pipe extending from a source of supply and which maybe exposed to freezing temperatures. In countries subject to freezingtemperatures, there are a great many water pipe systems which are notnormally protected from the low temperatures. At present, it is commonpractice to shut the water off from these systems when they are notrequired or when there appears to be a possibility of a sharp drop intemperature. One type of piping of this nature, is a iire fightingsystem including hydrants spread throughout a building. In warehouses,piers and the like, the buildings are not heated so that a drop intemperature below freezing is liable to freeze the water in the pipes,causing them to burst. Usually, these systems have a shut-ofi valve nearthe point where they connect with the source of supply, such as, thewater main. In cold weather, these valves are shut off, but the waterremains in the pipes. This means that a substantial drop in temperatureresults in burst pipes.

The main purpose of this invention is to provide apparatus forautomatically draining a water pipe when it is shut off from the sourceof supply. As this apparatus acts automatically, there is no danger ofthe system being left with water in it.

The apparatus is described and claimed herein in connection with a waterpipe, but it is to be understood that the term water pipe" is intendedto include one or more pipes which may form a complete system.

In order to protect a water pipe from damage due to low temperatures, ashut-oi! valve is provided between the pipe and its source of supply. Abranch pipe is connected to the water p pe. at each low point thereof,and a valve chamber is connected to each branch pipe. An outlet isformed in the chamber, and a release valve is provided therein whichnormally closes the outlet. This valve is retained in closed position bythe pressure of the water in the chamber. Suitable means is provided foropening the release valve as the water pressure drops when the shutoffvalve is closed.

An example of this invention is illustrated in the accompanying drawingsin which,

Figure 1 is a diagrammatic view of a water pipe and the drainingapparatus,

Figure 2 is a longitudinal valve apparatus,

Figure 3 is a section taken on the line 3-3 of Figure 2, and

Figure 4 is a section taken Figure 2.

section through the on the line 4-4 or Referring more particularly toFigure 1 of the drawings, l isa water pipe which is connected to asuitable source of supply, such as a water main I l, and this pipe hasone or more relatively low points l2 from which it is to be drained. Ifthis pipe is part of a fire protection system, pipes l3 may extend tohydrants which should be located above the pipe II].

A shut-off valve I6 is provided in the pipe l0 preferably near the mainll. An air valve ll of any suitable construction may be provided in thepipe adjacent a shut-off valve, although this is not absolutelynecessary. One or more drain valves are provided, each being connectedto the pipe II] by a branch pipe 2|. These valves are connected to thewater pipe at low points thereof in order to be sure that water woulddrain towards the valves. Figures 1 to 4 illustrate one form of drainvalve 20. This device consists oi a chamber which is connected to the.water pipe ID by a branch pipe 2|. This chamber has an inlet throughwhich water from the pipe may enter the chamber, and an outlet 26:formed therein. A release valve is provided in the chamber for normallyclosing the outlet. In this example, a release valve 28 is hingedlymounted at 29 in the chamber and is normally retained in closed positionover the outlet by the pressure of the water in the chamber. Suitablemeans is provided for opening the valve as soon as the water pressuredrops below a predetermined point. This takes place when the shut-offvalve I6 is closed.

In this example, a tube 30 extends outwardly from the chamber 25 overthe outlet 26. A rod 3| extends longitudinally of the tube and isfixedly mounted therein by any suitable anchoring means, such as, bymeans of pins 32 which extend through the tube and the rod. This rod isthreaded at its outer end as at 33, and said outer end preferablyextends beyond the end of the tube. A spring 35 is mounted on this rodand bears against the release valve 28. A nut 36 is threaded on theouter end of the rod and is adapted to be turned to adjust the pressureon the spring. In this example, an elongated sleeve 39 is mounted on therod and extends between the rod and the spring. The sleeve is providedwith slots 40 through which the anchoring pins 32 extend. These slotsmay open outwardly at the inner end of the sleeve in order to facilitatethe assembly of the device. If desired, a bearing 4! may be placed onthe rod between the spring and the sleeve in order to prevent the formerfrom being caught in the open ended slots of the latter. An additionaloutlet 42 is located in the 3 bottom of the pipe 30 adjacent the outlet26. This is to stop rust from being washed into the sleeve 39 andpreventing it from sliding on the rod 3|.

In use, the nut 36 of each drain valve 20 is turned until the pressureof the spring 35 on the valve 28 is a little less than the lowestpressure usually encountered in the water pipe I0, As the pressure inthe chamber 25 is the same as that in the water pipe, the release valveis normally retained in its closed position. When the temperature dropsto a point where there is anger of the water in the pipe freezing, theshut-off valve [6 is closed. This shuts the water pipe and each valvechamber 25 off from the pressure of the main so that there isa-considerable drop in the pressure in the chamber. At this time, thepressure of the spring 35 is suflicient to open the release valve, andthis allows the water to drain from the outlet 26 of the chamber 25 andthrough the outlet 4| of the tube 30. As long as the valve I6 is closed,the release valve will re.- main open so that the pipe l2 will bedrained. These drain valves not only open automatically, but they alsoclose automatically. As soon as the valve I6 is opened, the water pipeand the drain valves are filled with water at the pressure of the mainand this closes each release valve 28.

If the air valve I! is employed, it is opened as soon as the drain valveis closed sothat the pipe will be drained a little faster than itotherwise would. The air valve is closed when the shut-oit valve isopened.

The drain valve 20 is very easily adjusted to suit the pressure of anywater system, When the nut 36 is turned in one direction, the sleeve 39is moved inwardly to compress the spring 35. This may be done until thevalve 28 is opened slightly, which is indicated by a leakage of waterthrough the tube 30. Then the nut may be backed off just sufiiciently topermit the release valve to close, and the device is set for operation.

An important feature of this drain apparatus is its simplicity. It ispractically impossible for it to go out of operation. The valve 28 hangssubstantially in a vertical plane from it hinge point so that itnaturally tends to close. It is hardly likely that any dirt will restbetween the valve and its seat. However, if this did take place, therewould be a leakage of water through the chamber outlet and the releaseof pressure would enable the spring 35 to open the valve. In thesecircumstances, the valve usually opens and closes a few times and thisdislodges any foreign matter which may be caught therein.

What I claim as my invention is:

Apparatus for draining a water pipe extending from a source of supplyand which may be exposed to freezing temperatures, comprising a valvechamber having an inlet formed therein to be connected to a water pipeand through which water from said pipe may enter the chamber saidchamber having an outlet formed therein, a release valve ,hingedlymounted in the chamber normally retained in closed position over theoutlet by the pressure of water in the chamber, a tube extendingoutwardly from the chamber over the outlet, a rod extendinglongitudinally of the tube and beyond the outer end thereof, said rodbeing threaded at its outer end, anchoring means between the tube androd to hold the latter in position, a spring on the rod bearing againstthe release valve, a nut threaded on the outer end of the rod, and asleeve on the rod extending between the nut and spring, said sleevehaving slots therein through which the anchoring means extend, and saidspring being adapted to open the release valve when the water pressurein the chamber drops below a predetermined point.

PAUL W. ROBERTS.

REFERENCES CITED The following references are of record in the file ofthis patent:

